Fluidic generator with velocity discrimination

ABSTRACT

Air is caused to simultaneously enter an inner nozzle in which a cylindrical plug is centrally located to form an annular orifice, and an outer nozzle in which fluid resistors are located to limit the maximum fluid pressure therein. The air discharging from the outer nozzle interferes with the air emanating from the annular orifice until such time as the fluid pressure from the latter is greater than that from the former. After that time, the air discharging from the annular orifice impinges directly on the edge of a resonating cavity producing a multiple frequency edgetone. The column of air in the resonating cavity is thereby caused to vibrate at a frequency determined by the depth of the cavity. The changes in pressure within the resonating cavity cause a diaphragm forming an end of the cavity to pulsate inwardly and outwardly. A rod is attached to the diaphragm, and this rod transmits the vibrations of the diaphragm to a metallic reed which will then oscillate between a pair of magnetic pole pieces. The oscillations of the reed will induce an electromotive force in a coil. The electromotive force induced in the coil may be made available to provide energy to operate an external electrical circuit.

D United StatesPatent 1 3,568,704

[72] Inventors ClrlJ. Campagnuolo 3,515,093 6/1970 Greene 137/81.5X Potomac; 3,515,158 6/1970 Utz l37/81.5 A 1 No Primary Examiner-Samuel Scott AttorneysHarry M. Saragovitz, Edward J. Kelly, Herbert [22] Filed Aug. 27,1969 Bed and J D Ed t 451 Patented Mar. 9, 1971 [73] Assignee The United States of America as represented by the secretary Navy ABSTRACT: Air is caused to simultaneously enter an inner nozzle in which a cylindrical plug is centrally located to form [54] FLUIDIC GENERATOR WITII VELOCITY an annular orifice, and an outer nozzle in which fluid resistors DISCRIMINATION are located to limit the maximum fluid pressure therein. The 3 chims I III-WI.g g air discharging from the outer nozzle interferes with the air emanating from the annular orifice until such time as the fluid [52] US. Cl. l37/8L5 pressure f the latter is greater than that f the f After that time, the air discharging from the annular orifice F159 4/00 impinges directly on the edge of a resonating cavity producing [50] Field of Search -l37/8l.5 a lti le frequency edgetone. The column of air in the resonating'cavity is thereby caused to vibrate at a frequency [56] Ream Cited determined by the depth of the cavity. The changes in pres- UNITED STATES PATENTS sure-withinthe resonating cavity cause a diaphragm forming 3,039,490 6/ 1962 Carlson, Jr. l37/81.5 an end of the cavity to pulsate inwardly and outwardly. A rod 3,398,758 8/1968 Unfried 137/8l.5 is attached to the diaphragm, and this rod transmits the vibra- 3,451,41 l 6/1969 Johnson 137/8 1 .5 tions of the diaphragm to a metallic reed which will then oscil- 3,454,025 7/1969 Egli l37/81.5 late between a pair of magnetic pole pieces. The oscillations of 3,489,161 l/ 1970 Rexford. l37/81.5X the reed will induce an electromotive force in a coil. The elec- 3,500,850 3/1970 Kelley l37/81.5 tromotive force induced in the coil may be made available to 3,503,440 3/1970 Richards 137/8 1 .5 provide energy to operate an external electrical circuit.

FLUIDIC GENERATOR WITH VELOCITY DISCRIMWATION RIGHTS OF THE GOVERNMENT The invention described herein may be manufactured, used, and licensed by or for the US. Government for governmental purposes without the payment to us of any royalty thereon.

BACKGROUND OF INVENTION This invention relates to an improvement in a device known as a fluidic generator which transforms pneumatic energy into electrical energy. More particularly, the present invention provides a fluidic generator which will function only after a predetermined input pressure has been reached.

The instant invention is an improvement upon the fluidic generator disclosed in, US. Pat. application No. 745,949 filed Jun. 17, 1968 by Campagnuolo et al. and possesses all the advantages of that device as well as other and additional advantages apparent from the disclosures hereinafter.

It would be advantageous to be able to control the'fluidic generator in such a manner as to switch it ON only after a certain input fluid pressure is reached. This control is accomplished by providing a fluid control steam to the generator of the aforesaid application.

'One example of a situation in which the aforesaid control means are desirable is in providing controllable power supplies for electronic fuzes in missiles and projectiles. The fluidic generator of the? aforesaid application provides electrical power at the instant ram air is introduced through the entrance duct. However, an important safety requirement in many such applications is that the electronic fuzing system of the projectile must remain inoperative until a certain distance is reached from the launching area. This is to protect the personnel engaged in the launching operation from possible injury resulting from a premature detonation of theprojectile.

It is therefore an object of this invention to provide an improved fluidic generator which acts as' avelocity discriminator in addition to a power supply.

An additional object of this invention is to provide a fluidic generator for projectiles that will operate only after a certain preset flight velocity is attained.

It is a further object of this invention to provide to a fluidic generator a safety feature which prevents a premature electronic activation of a projectile in which the generator is housed.

SUMMARY OF THE INVENTION The aforementioned and other objects may be obtained by using a fluid oscillator in which a diaphragm is an integral part of the oscillator resonating cavity and by directing the fluid which is the source of power of the oscillator directly toward the cylindrical opening of the resonating cavity through an entrance chamber from an annular orifice and by directing into the entrance chamber-another fluid supply carried by a control conduit to interact with the fluid from the annular;orifice. Subsequent action will begin onlyafter the fluid pressure from the annular orifice surpasses the pressure from the control BRIEF DESCRIPTION OF THE DRAWING The specific nature of the invention as well as other objects, aspects, uses, and advantages thereof .will clearly appear from the following description and from the accompanying drawing, in which:

The drawing is an oblique, partially cutaway view of a preferred embodiment of the improved fluidic generator with velocity discrimination of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT 1 opening and a main channel 50 formed by an inner cylinder l 1. At the endof inner cylinder 11 opposite port 10 a cylindrical plug 12 is centrally located therein forming an annular orifice 14, beyond which is an entrance chamber 22 formed by a conduit 16 whichhas openings 18 therein for exhaust purposes. Fluid is also. received'in entrance chamber 22 through an opening 17 from control conduit 40 which is formed by outer, cylinder 13 and inner cylinder 11. Entrance chamber 22 leads to an opening 21 in a resonating cavity 20 whose other end is enclosed by a diaphragm 23. Attached to diaphragm 23 by means of a rod 24 is a metallic reed armature 25 whose free end is centrally located in a magnetic coil 26. between two permanent magnet pole pieces of opposite polarity 30 and 32. A pair of wires 34 are attached to coil 26 to couple the voltage generated by the fluidic generator to an external electrical circuit.

In operation, air, which is the source of power, enters the generator at port 10-. In the case of a flying projectile this will be the ram air entering the nose of the projectile. The main portion of the column of air entering port 10 is converted by annular orifice 14 into an annular column which proceeds into entrance chamber 22. Annular orifice 14 is of a slightly smaller diameter than opening 21, but the columns of air emanating from orifice 14 will tend to spread and impinge upon the edge of opening 21. The impinging of the air of this edge, in the well known manner, will produce a multiple frequency edgetone or ringtone. The oscillation of the annular column of air back and forth across the end of opening 21 will cause the column of air in the resonating cavity to vibrate, with the frequency of that vibration beingdetermined by the depth of cavity 20. The vibration of air in cavity 20 will in turn cause diaphragm 23 to pulsate inwardly and outwardly. The excess air in column 16 is exhausted to the atmosphere through vents 18. The pulsations of diaphragm 23 are transmitted by means of rod 24 to armature 25 which is then caused to oscillate between magnetic pole pieces 30 and 32. The oscillations of armature 25 will induce an electromotive force in coil 26; this emf can then be coupled to an external circuit through wires 24. v

However, the velocity discrimination device of the present invention delays the aforesaid actions in the following manner. A portion of the initial column of air entering port l0'is diverted through control conduit 40 to opening 17 and impinges upon the main jet of air from annular orifice 14 in entrance chamber 22, diverting the main jet and thus preventing the cavity 20 from resonating so that no pressure fluctuations impinge upon the diaphragm 23. The system will produce oscillations only when the fluid pressure emanating from annular orifice 14-becomes large enough to overcome the fluid pressure from opening 17. The transition point at which the fluid pressure of the annular column overcomes that from opening 17 can be accurately established by limiting the maximum pressure which can propagate in control conduit 40. This may be done by placing in control conduit 40 wellcalibrated fluid resistors19 as, for example, constricting pads, variable needle valves, and the like.

Hence, by the aforesaid arrangement it is possible to cause operation of the fluid generator at a required velocity or pres-. sure corresponding, for example, to a particular position in a projectiletrajectory. Therefore, the control conduit 40 provides the fluid generator with velocity discrimination, an im-' portant safety feature in fuzing systems.

We wish it to be understood that we do not desire to be limited to the exact details of construction shown and from said common source, transform said fluid into an an nular column and direct said annular column of fluid through said entrance chamber directly into and so as to .impinge upon an edge of said open end of said enclosed volume so as to produce a multiple frequency edgetone thereby causing the fluid in said enclosed volume to vibrate at a predetermined frequency;

d. velocity'discrimination means utilizing a portion of fluid from said common source for preventing the fluid in said enclosed volume from vibrating until a predetermined pressure level of said annular column of fluid is attained;

e. mechanical means for sensing the vibrations of said enclosed volume; and

f. generating means for translating the vibrations sensed by said mechanical means into electrical energy.

2. The apparatus of claim 1 wherein said velocity discrimination means comprises a control conduit directing a portion of fluid issuing from said common source directly into said entrance chamber to interact with said annular column of fluid whereby the fluid pressure from said annular column must overcomethe fluid pressure from said control before said vibrations can occur.

.3. The apparatus of claim 2 wherein said predetermined pressure is set .by adjustable fluid resistors placed in said control conduit to limit the maximum pressure of the fluid that can propagate therein.

P041050 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,5 8,7 Dated March 9, @97

n n 0 Carl J. Campagnulo and Henry C. Lee

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In column l, line 15, insert the word conduit after the word "control."

Signed and sealed this 22nd day of June 1971.

(SEAL) Attest:

EDWARD M.FLETCHER, JR. Attesting Officer WILLIAM E. SCHUYLER, JR. Commissioner of Patents 

1. Apparatus for utilizing fluid flow to generate electrical energy comprising, in combination: a. a main channel adapted to provide a common source of fluid; b. an entrance chamber leading to an enclosed volume having an open end and a closed end and defining a resonant cavity; c. an annular orifice adapted to receive a portion of fluid from said common source, transform said fluid into an annular column and direct said annular column of fluid through said entrance chamber directly into and so as to impinge upon an edge of said open end of said enclosed volume so as to produce a multiple frequency edgetone thereby causing the fluid in said enclosed volume to vibrate at a predetermined frequency; d. velocity discrimination means utilizing a portion of fluid from said common source for preventing the fluid in said enclosed volume from vibrating until a predetermined pressure level of said annular column of fluid is attained; e. mechanical means for sensing the vibrations of said enclosed volume; and f. generating means for translating the vibrations sensed by said mechanical means into electrical energy.
 2. The apparatus of claim 1 wherein said velocity discrimination means comprises a control conduit directing a portion of fluid issuing from said common source directly into said entrance chamber to interact with said annular column of fluid whereby the fluid pressure from said annular column must overcome the fluid pressure from said control before said vibrations can occur.
 3. The apparatus of claim 2 wherein said predetermined pressure is set by adjustAble fluid resistors placed in said control conduit to limit the maximum pressure of the fluid that can propagate therein. 